Early Ventilator-Associated Pneumonia in Patients on Outpatient Acid-Suppressive Therapy

Abstract

PURPOSE: Purpose: To evaluate whether patients on outpatient acid-suppressive therapy (AST) have a higher incidence of early VAP than patients not on AST prior to admission. METHODS: Retrospective review of data collected from the Project Impact database on intubated patients in the ICU over a five year period. The Early VAP group was defined as those with a diagnosis of pneumonia >2 and <11 days after hospital admission. A set of age and gender matched controls (those without early VAP) were generated on a 3:1 basis with the VAP group and seasonally matched as well. A chart review was conducted on both groups to identify outpatient medications to ascertain outpatient AST. Differences in outpatient AST were compared between groups. Subgroup analysis was performed to compare types of AST (PPI and H2B) between early VAP and non-early VAP groups. Categorical variables were compared using Pearson' s Chi-Square. RESULTS: A total of 444 patients were included (110 in the early VAP group and 334 in the non-early VAP group). AST in the early VAP group was 31.8% (35/110) versus 17.1% (57/334) in the non-early VAP group (p = 0.0009). Subgroup analysis showed that outpatient PPI therapy in the early VAP group was 19.0% (21/110) versus 13.8% (46/334) in the non-early VAP group (p = 0.18); outpatient H2B therapy in the early VAP group was 12.7% (14/110) versus 3.3% (11/334) in the non-early VAP group (p = 0.0002). CONCLUSION: Outpatient AST appears to be a significant risk factor for the development of early VAP in ICU patients. Furthermore, outpatient H2B therapy may put intubated ICU patients at greater risk of developing early VAP compared to outpatient PPI therapy. CLINICAL IMPLICATIONS: These findings reinforce the importance of specific aspects of the ventilator bundles (notably head of bed elevation). In addition they suggest that patients on outpatient AST require increased vigilance for the development of VAP. Consideration should be given to investigating the application of interventions such as selective decontamination protocols, specifically in this patient population.